Organic Electroluminescent Display Panel

1. An organic electroluminescent (EL) display panel comprising a display element including a pixel electrode and a pixel circuit which includes: a first transistor having a main electrode and a control electrode, and configured to output a current corresponding to a voltage between the main electrode and the control electrode to the pixel electrode of the display element; a second transistor having a main electrode and a control electrode coupled to the control electrode of the first transistor; and a third transistor for applying a data line voltage from a data line to the second transistor in response to a select signal provided by a current scan line, the organic EL display panel comprising: a power electrode line substantially in parallel with the data line, and coupled to the main electrode of the first transistor; and a control electrode line comprising a first portion substantially aligned with and coupled to the control electrode of the first transistor and the control electrode of the second transistor and a second portion coupled to the first portion, the second portion extending substantially parallel to the power electrode line and overlapping at least a portion of the power electrode line for at least a whole length of the pixel electrode to form a capacitor between the main electrode and the control electrode of the first transistor, wherein the control electrode line is coupled to the main electrode of the second transistor so as to diode-connect the second transistor, wherein a channel of the first transistor and a channel of the second transistor are formed substantially in parallel with the current scan line.

2. The organic EL display panel of claim 1 , wherein the first portion of the control electrode line for coupling the control electrode of the first transistor to the control electrode of the second transistor extends in a direction substantially perpendicular to that of the current scan line.

3. The organic EL display panel of claim 1 , wherein the capacitor is formed substantially in parallel with the data line, and the display element is at a region between the capacitor and the data line.

4. The organic EL display panel of claim 1 , wherein the first, second, and third transistors have the same channel type.

5. An organic electroluminescent (EL) display panel comprising a display element including a pixel electrode and a pixel circuit which includes: a first transistor having a main electrode and a control electrode, and configured to output a current corresponding to a voltage between the main electrode and the control electrode to the pixel electrode of the display element; a second transistor having a control electrode coupled to the control electrode of the first transistor; and a third transistor for applying a data line voltage from a data line to the second transistor in response to a select signal provided by a current scan line, the organic EL display panel comprising: a power electrode line substantially in parallel with the data line, and coupled to the main electrode of the first transistor; a control electrode line comprising a first portion substantially aligned with and coupled to the control electrode of the first transistor and the control electrode of the second transistor and a second portion coupled to the first portion, the second portion extending substantially parallel to the power electrode line and overlapping at least a portion of the power electrode line for at least a whole length of the pixel electrode to form a capacitor between the main electrode and the control electrode of the first transistor; and a fourth transistor for applying a pre-charge voltage to a main electrode of the second transistor and the control electrode of the first transistor in response to a control signal, wherein a channel of the first transistor and a channel of the second transistor are formed substantially in parallel with the current scan line.

6. The organic EL display panel of claim 5 , wherein the fourth transistor is located on an opposite side of the first transistor with respect to the display element.

7. An organic electroluminescent (EL) display panel comprising a display element including a pixel electrode and a pixel circuit which includes: a first transistor having a main electrode and a control electrode, and configured to output a current corresponding to a voltage between the main electrode and the control electrode to the pixel electrode of the display element; a second transistor having a control electrode coupled to the control electrode of the first transistor; a third transistor for applying a data line voltage from a data line to the second transistor in response to a select signal provided by a current scan line; and a fourth transistor for applying a pre-charge voltage to the control electrode of the first transistor in response to a select signal provided by a previous scan line, the organic EL display panel comprising: a power electrode line substantially in parallel with the data line, and coupled to the main electrode of the first transistor; and a control electrode line coupled to a main electrode of the fourth transistor, the control electrode of the first transistor, and the control electrode of the second transistor, the control electrode line comprising a portion that extends substantially parallel to the power electrode line and overlapping at least a portion of the power electrode line for at least a whole length of the pixel electrode to form a capacitor between the main electrode and the control electrode of the first transistor, wherein a channel of the first transistor and a channel of the second transistor are formed substantially in parallel with the current scan line.

8. The organic EL display panel of claim 7 , wherein a portion of the control electrode line for coupling the control electrode of the first transistor to the control electrode of the second transistor is elongated in a direction substantially perpendicular to an extending direction of the current scan line.

9. The organic EL display panel of claim 8 , wherein the capacitor is formed substantially in parallel with the data line, and the display element is at a region between the capacitor and the data line.

10. The organic EL display panel of claim 8 , further comprising a fifth transistor for decoupling the first transistor from the display element in response to a control signal.

11. The organic EL display panel of claim 10 , wherein a channel of the fifth transistor is formed substantially in parallel with the data line.

12. An arrangement structure for a display panel comprising a display element including a pixel electrode and a pixel circuit which includes: a first transistor having a main electrode and a control electrode, and configured to output a current corresponding to a voltage between the main electrode and the control electrode to the pixel electrode of the display element; a second transistor having a control. electrode coupled to the control electrode of the first transistor; a third transistor for applying a data line voltage from a data line to the second transistor in response to a select signal provided by a current scan line; and a fourth transistor for applying a pre-charge voltage to the control electrode of the first transistor in response to a select signal provided by a previous scan line, the arrangement structure comprising: a power electrode line substantially in parallel with the data line, and coupled to the main electrode of the first transistor; and a control electrode line coupled to a main electrode of the fourth transistor, the control electrode of the first transistor, and the control electrode of the second transistor, the control electrode line comprising a portion that extends substantially parallel to the power electrode line and overlapping at least a portion of the power electrode line for at least a whole length of the pixel electrode to form a capacitor between the main electrode and the control electrode of the first transistor, wherein a channel of the first transistor and a channel of the second transistor are formed substantially in parallel with the current scan line, and a portion of the control electrode line for coupling the control electrode of the first transistor to the control electrode of the second transistor is elongated in a direction substantially perpendicular to an extending direction of the current scan line.

13. The arrangement structure of claim 12 , wherein the first, second, third, and fourth transistors have the same channel type.

14. An organic electroluminescent (EL) display panel comprising a plurality of scan lines, a plurality of data lines, a plurality of control electrode lines, a plurality of power electrode lines and a plurality of pixel circuits, each said pixel circuit coupled to a corresponding said scan line, a corresponding said data line, a corresponding said control electrode line and a corresponding said power electrode line, and comprising: a display element comprising a pixel electrode; a first transistor having a main electrode coupled to the corresponding said power electrode line and a control electrode coupled to the corresponding said control electrode line, the first transistor for outputting a current corresponding to a voltage between the main electrode and the control electrode to the pixel electrode of the display element; a second transistor having a control electrode coupled to the control electrode of the first transistor; and a third transistor coupled to the corresponding said scan line and the corresponding said data line for applying a data line voltage from the corresponding said data line to a main electrode of the second transistor in response to a select signal provided by the corresponding said scan line, wherein at least a portion of the corresponding said control electrode line extends substantially parallel to the corresponding said power electrode line and overlaps at least a portion of the corresponding said power electrode line for at least a whole length of the pixel electrode to form a capacitor between the main electrode and the control electrode of the first transistor.

15. The organic EL display panel of claim 14 , wherein a portion of the corresponding said control electrode line for coupling the control electrode of the first transistor to the control electrode of the second transistor is elongated in a direction substantially perpendicular to an extending direction of the corresponding said scan line.

16. The organic EL display panel of claim 14 wherein the capacitor is formed substantially in parallel with the corresponding said data line, and the display element is at a region between the capacitor and the corresponding said data line.

17. The organic EL display panel of claim 14 , wherein the second transistor is diode-connected and each said pixel circuit further comprises a fourth transistor coupled between a pre-charge voltage and the control electrode of the second transistor to provide the pre-charge voltage to the control electrode of the second transistor in response to a select signal provided by a previous said scan line.

18. The organic EL display panel of claim 17 , further comprising a fifth transistor coupled between the first transistor and the display element to electrically decouple the first transistor from the display element in response to a control signal from a corresponding one of a plurality of control lines in the organic EL display panel.

19. The organic EL display panel of claim 14 , wherein a channel of the first transistor and a channel of the second transistor are formed substantially in parallel with the corresponding said scan line.